Koseki Translation (戸籍謄本): Japan's Family Register for USCIS

The koseki (戸籍, family register) is Japan's foundational civil-registration document. Rather than issue separate birth, marriage, death, divorce, and adoption certificates the way most countries do, Japan records every one of those vital events for its citizens in a single household-based register. The U.S. State Department's reciprocity schedule confirms that for each of these events the obtainable Japanese civil document is the family register — or the matching Certificate of Acceptance of Notification issued at the time of the event.

The register is keyed to a 本籍 (honseki, registered or permanent domicile) — not a current residential address — and is maintained at the municipal (city, ward, town, or village) office of that domicile. The honseki is a symbolic legal "roots" address that need not be where the family actually lives, which is one of the most important facts a translator has to handle correctly.

Each register is anchored by a 筆頭者 (hittosha), the person listed first at the head of the register, with every other member listed by their 続柄 (zokugara, relationship to that head). Only Japanese citizens appear in a koseki; a foreign spouse is never entered as a register member and is instead noted within the Japanese person's record.

For immigration purposes the koseki matters because it documents parent-child and spousal links directly, in an official government register. That is exactly what makes it the standard Japanese civil-record evidence of a family relationship. When you need a certified koseki translation prepared to USCIS standards, the family register is the document at the center of the filing.

A koseki opens with register-level matters (戸籍事項, koseki jiko) — such as when this particular register was created or reformed and the honseki it is keyed to — followed by an entry for each member, beginning with the head of the register.

Every member entry records the same core fields: 氏名 (shimei, full name — surname plus given name), 生年月日 (seinengappi, date of birth in Japanese era format), and 続柄 (zokugara, relationship to the head). Beneath those sit the recorded events that happened to that person, each with its own date, place, and notifier.

The event entries are the heart of the document. They include 出生 (shussei, birth), 婚姻 (konin, marriage), 離婚 (rikon, divorce), 死亡 (shibo, death), and 養子縁組 (yoshi engumi, adoption — the creation of an adoptive parent-child relationship). Because these are all written into the same register, one koseki can simultaneously serve as the birth record, the marriage record, and the death record for the people listed in it.

The relationship field uses zokugara terms that encode more than English does. 妻 (tsuma) is wife; 長男 (chonan) is eldest son; 長女 (chojo) is eldest daughter; 二男 / 次男 is second son; 養子 (yoshi) is an adopted child. These values carry birth order and adoptive status that a translator must preserve rather than flatten to a bare "son" or "child."

Finally, the register carries the issuing municipality's seals and certification stamps. These print black on the black-and-white scans clients usually submit — so the translator describes the seal text where legible and notes its placement instead of inventing a "round red seal."

Not every "koseki" is the same document, and choosing the wrong variant is a frequent cause of delays. The full copy is the 戸籍謄本 (koseki tohon), known in the computerized format as the 全部事項証明書 (zenbu jiko shomeisho, "certificate of all matters"). It reproduces the entire current register — all members and all recorded events — and is the standard choice for USCIS family-relationship evidence because it shows the full household context.

The extract is the 戸籍抄本 (koseki shohon), or 個人事項証明書 (kojin jiko shomeisho, "certificate of individual matters") in the digital format. It covers only one named individual. An extract can be insufficient when the adjudicator needs to see how two people relate within the register, which is why the full tohon is usually the safer submission.

Older events may not appear on the current register at all. The State Department notes that past records may not carry over when a municipality changes its record system or when the head of family changes domicile. When that happens, the event lives in a closed or prior-format register: a 除籍 (joseki) tohon/shohon is a copy of a closed register where every member has left by death, marriage, or transfer, while a 改製原戸籍 (kaisei-genkoseki) is the original pre-reform register that was superseded by computerization.

There is also an event-specific alternative that is not the register itself: a Certificate of Acceptance of Notification — for example 婚姻届受理証明書 (konin todoke juri shomeisho) for marriage or 出生届受理証明書 (shussei juri shomeisho) for birth. This is the document that records an event for a non-Japanese person, who is never a koseki member, and it is retained only for a limited period.

The U.S. Embassy in Japan specifically directs applicants whose current koseki does not show the place of birth to obtain the register that was in effect at the time of birth — in practice a joseki or kaisei-genkoseki. Knowing which variant you actually hold determines whether your packet proves what it needs to. When you are unsure which copy to file, our certified koseki tohon translation service starts from the exact pages you hold.

For a USCIS family-based petition involving a Japanese national, the koseki is the standard Japanese civil-record evidence of the qualifying relationship. Because Japan issues no standalone birth or marriage certificate, the family register is the official record itself — for a spouse petition it functions as the marriage record, and for a parent-child petition (a parent petitioning for a child, or a child for a parent) it functions as the birth and parentage record.

The State Department reciprocity schedule lists the Koseki Tohon/Shohon (or the matching Certificate of Acceptance of Notification) as Available and acceptable for birth, marriage, death, divorce, and adoption. Because the schedule lists these as Available, the koseki is the primary civil-document evidence of the relationship — it is the official record, not a substitute for one. On a Form I-130, a spouse petition needs the marriage record and a child petition needs the birth record showing parentage, and the koseki is what supplies both for a Japanese filing. Our family petition document translation prepares the register to that standard.

The U.S. Embassy in Japan's immigrant-visa guidance states that an applicant must submit an original or certified copy of the family register showing date and place of birth and parentage, accompanied by a translator-certified English translation. It notes that the register does not expire so long as the information is still correct, but recommends a copy issued within three months. If the current koseki does not show the place of birth, the embassy directs the applicant to obtain the register in effect at the time of birth.

All foreign-language documents filed with USCIS must carry a full English translation with the translator's certification of completeness, accuracy, and competence under 8 CFR 103.2(b)(3). The koseki is also commonly submitted with Form I-485 (adjustment of status) when filed in the United States.

One firm limit: a certificate of residence (住民票, juminhyo) and religious-organization certificates are expressly not acceptable in lieu of the family register. The juminhyo is a separate residence record and does not carry the relationship and event data that make the koseki evidentiary.

The koseki concentrates several features that have no clean English equivalent, plus dense formatting and official seals. These are the points a specialist watches:

Japanese era dates: every date uses 令和 / 平成 / 昭和 (Reiwa / Heisei / Showa) plus an era-year. Best practice is to render the Gregorian date and preserve the original era notation. The conversion is Reiwa + 2018, Heisei + 1988, Showa + 1925 — but era-transition years must be handled carefully, since 1989 was both Showa 64 and Heisei 1, and 2019 was Heisei 31 then Reiwa 1 from May 1.

Name romanization: spelling must match the Hepburn romanization on the beneficiary's Japanese passport exactly, including long-vowel handling (Yuki vs Yūki vs Yuuki, Ohno vs Ono). Inconsistent spelling across documents is a classic identity-mismatch trigger. Where a kanji reading is ambiguous, the katakana furigana now recorded under the Revised Family Register Act (effective May 26, 2025) can help — though it is present only once the reading has been notified or entered, so many existing and older registers still give kanji only.

Honseki vs address: 本籍 is the registered or permanent domicile, not a current residence, and must be translated as "registered/permanent domicile" — never mislabeled "address." Conflating it with the actual residence (which lives on the separate 住民票/juminhyo) is a substantive error, not a stylistic one.

Relationship terms (続柄): values like 長男 (eldest son), 長女 (eldest daughter), 二男/次男 (second son), and 養子 (adopted child) encode birth order and adoptive status with no single English word. They are translated descriptively and the legally significant adoptive distinction is preserved.

Head-of-register concept (筆頭者): there is no exact English equivalent, so it is rendered as "head of the family register" or "first-listed person," avoiding loaded terms like "head of household" that imply current cohabitation.

Seals, side-notes, and layout: every seal, marginal/side note, and reverse-side line must be translated or marked [illegible] — omissions are a leading RFE cause. On black-and-white scans seals print black, so the seal text and placement are described rather than guessed. The English version mirrors the koseki's dense grid and translates every line without compressing it.

Archival registers: joseki and kaisei-genkoseki copies use vertical writing, archaic or variant kanji forms, and historical place names, which raise legibility and transliteration difficulty that a generalist often gets wrong.

These are the recurring errors that get a koseki translation questioned or strip it of evidentiary value:

Calling it a "birth certificate" or "marriage certificate": Japan does not issue those as standalone documents. Labeling the register as if it were one misrepresents what it is — the koseki is the record for multiple events at once.

Submitting a shohon when a tohon is needed: filing the individual extract (戸籍抄本 / 個人事項証明書) when the full register is required to show the relationship context leaves out the very members the adjudicator needs to see.

Translating 本籍 as the current "address": confusing the registered domicile with the residence record (住民票) is a substantive error that misstates a key field.

Omitting seals, side-notes, or reverse-side text: dropping any stamp, marginal note, or back-of-page line makes the translation incomplete and is one of the most common reasons USCIS issues a Request for Evidence.

Name spelling that does not match the passport: any deviation from the passport's Hepburn romanization invites identity-mismatch review.

Leaving dates in era form or mis-converting them: rendering only 令和/平成/昭和 dates, or fumbling an era-transition year, produces dates an adjudicator cannot verify.

Assuming a foreign spouse "appears in" the koseki: foreigners are not register members; they are only noted in the Japanese person's record, and a foreigner's own event may instead be documented by a time-limited Certificate of Acceptance of Notification.

Self-translation or weak certification: a translation by the petitioner or beneficiary, or generic certification wording, undermines credibility and the 8 CFR 103.2(b)(3) requirement. Not retrieving an older register (joseki / kaisei-genkoseki) when the current koseki no longer shows a needed past event, such as the place of birth, is the other frequent omission.